Thousands of mature, native ash trees are being dug up and burned after the devastating disease ash dieback was confirmed in Devon.

About 2,000 trees at Byway Farm near Tiverton are affected, according to the Forestry Commission.

This is the first confirmed case of the disease in mature, native trees in the region – another nine cases have been confirmed in young trees that have been recently planted at sites across Devon and Cornwall, including two sites on Dartmoor National Park, according to Forestry Commission figures.

Ben Jones, of the commission’s England plant protection team, said: “It appears that the affected trees had the disease when they were planted in 1996-97. It is concerning and we are continuing our investigations into how the spread had taken place and how far it has spread.”

http://www.westernmorningnews.co.uk/Trees-burned-infection-ash-dieback/story-19481835-detail/story.html

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Dutch elm disease is a tragic thing to watch, but we shouldn’t be too gloomy. Woody vegetation responds, adapts, regroups. What emerges in its recovery stage may not be the same as before, but it will always be a vital, dynamic, arboreal community.

The fungus, now known as Chalara fraxinea, is biologically mysterious, an entirely new organism of uncertain origins. It probably evolved in eastern Asia, where it appears to be harmless to native ash species. Its ancestor is a benign and widespread leaf fungus called Hymeno­scyphus albidus, native even in the UK. But at some recent date, this threw up a mutant, Hymenoscyphus pseudoalbidus, with slight genetic differences but a terrible virulence.

Natural resistance is likely to be the best hope for the survival of a core population of ashes in the UK. Isolated from the continent for nearly 8,000 years, our trees may be more genetically diverse than those in Poland.

For their part, ordinary rural people were mystified by the need for plantations, having lived for thousands of years with woods that renewed themselves spontaneously and indefinitely by seeding, or by regrowth from cut coppice stools and pollards. In place of this system of natural regeneration came the notion of trees as artefacts, biddable machines for the production of timber, programmed at every stage of their lives from planting to cutting.

The fundamental grammar of our relationship with them had been changed. Previously, “growing” had been an intransitive verb in the language of woods. Trees grew, and we, in a kind of subordinate clause, took things from them. In the forest-speak of the Enlightenment, “growing” became a transitive verb. We were the subject and trees the object. We were the cause of their existence in particular places on the earth.

Now, in the extremities of ash dieback, we can see that decades of well-intentioned planting have been not only often unnecessary, but, quite possibly, dangerous. Runtish saplings, often mislabelled and of unknown provenance, are shoved into the ground, regardless of whether they might be vectors for disease, or whether the soil is right and the site appropriate.

The existence of a large population of indigenous ashes is our best safeguard for the future and makes rather baffling the Forestry Commission’s experiment, initiated early in May, of planting out trial plots with 150,000 saplings of “15 different varieties”. The intention is to discover whether a few may be resistant and eventually propagate from them. But as 80 million ashes from probably ten times that number of genotypes are already engaged in just such an experiment across Britain, it is hard to see this as much more than a PR exercise – one that fits tidily in to our long, hubristic belief that the salvation of trees lies with us and our superior arboreal intelligence only.

http://www.newstatesman.com/sci-tech/2013/06/our-ash-trees-are-dying-dont-despair-catastrophes-are-natural-events-lives-trees

See also: http://worldwidewood.wordpress.com/2013/06/17/natural-ash-nursery-cleared-and-ready-for-the-deer-fence/

I am particularly excited that the Real Life Science Studio in the John Hope Gateway will be hosting the Virtual Landscape Theatre for one week from 8th August. This interactive exhibit allows an audience to decide what actions should be taken to reduce the impact of ash dieback and to explore the implications of these choices. Intrigued? Come and find out more in August!

Diseases are a real threat to our trees and it is likely we will loose a high proportion of our ash trees. Yet, over the course of this project I started to feel more positive about the future of Scottish woodlands. It would be easy to listen to the mass media and get very depressed about the state of our forests and trees. But woodlands are dynamic and have always changed; over such long periods of time we humans find it difficult to comprehend.

We need to build resilience in the woodlands of Scotland to ensure their longevity. By this I mean managing woodlands in a way that creates diversity in the species present, diversity in the age of the trees and diversity in structure. If we do this it may be possible to maintain the ever-changing, unique woodlands of Scotland.

http://stories.rbge.org.uk/archives/2051

We will rightly mourn the demise of ash trees from our woods, copses and country lanes if most of them succumb to deadly Chalara fungus. But the dead wood they will provide will be an enormous boost for Britain’s biodiversity. Dead wood is the richest habitat in a healthy forest. It supports a huge variety of wood-boring invertebrates, plus a battalion of fungi whose thread-like filaments penetrate deep inside to slowly decompose it, returning its nutrients to the forest soil.

A forest with plenty of dead timber provides a cornucopia of invertebrates for birds such as nuthatches, warblers and woodpeckers to feast on. And large dead trees, because rot holes more easily develop in them, are good places for hole-breeding species like bats, jackdaws and tawny owls.

If swathes of ash trees start dying Britain-wide, the policy of fell and burn to stop the spread of the fungus will serve no further purpose. Dead trees mustn’t be squandered.

http://www.independent.co.uk/voices/comment/mourn-the-passing-of-the-ash-tree-but-for-conservationists-there-is-a-silver-lining-8329356.html